BROOKLYN — Watch the live stream weigh-in for Saturday’s IBF welterweight title match between Errol Spence Jr. (22-0, 19 KOs) and Lamont Peterson (35-3-1, 17 KOs). The bout is Spence’s first defense of the title he won last May by stopping Kell Brook in 11 rounds. Peterson is competing in his first bout since defeating David Avanesyan by unanimous decision last February. The fight airs on Showtime January 20 at 9 p.m.